The present invention pertains to adjustable seat suspension systems having air bar suspensions for resiliently supporting the seat in any adjusted position and wherein control means are provided for the air bag to control the amount of flow of air admitted to or exhausted from the air bag. Many of these prior art devices have been proposed and used with a considerable amount of success, but some of them are extremely complicated as to the number of parts involved and as to their adjustabilities and settings. Other of these prior art devices did not provide a sufficiently wide range of seat adjustments for various sized operators, but instead provided only definite, fixed height settings. Seat suspension controlling devices of the kind to which the present invention is directed must be easy and foolproof in operation and not subject to malfunction of its parts.
One example of prior art devices of the general type to which the present invention relates is shown in the U.S. Pat. No. 3,325,136 which issued June 13, 1967 to A. O. Radke entitled "Seat Suspension."